/*
 * Copyright (c) 2006-2021, Ulandlink Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2022-11-20      wxl    first version
 */

#include <stdio.h>
#include <string.h>

#include <at_device_r6.h>

#if !defined(AT_SW_VERSION_NUM) || AT_SW_VERSION_NUM < 0x10300
#error "This AT Client version is older, please check and update latest AT Client!"
#endif

#define LOG_TAG							 "at.skt.r6"
#include <at_log.h>

#if defined(AT_DEVICE_USING_R6) && defined(AT_USING_SOCKET)

#define R6_MODULE_SEND_MAX_SIZE 1000

/* set real event by current socket and current state */
#define SET_EVENT(socket, event) 		(((socket + 1) << 16) | (event))

/* AT socket event type */
#define R6_EVENT_CONN_OK 				(1L << 0)
#define R6_EVENT_SEND_OK 				(1L << 1)
#define R6_EVENT_RECV_OK 				(1L << 2)
#define R6_EVNET_CLOSE_OK 				(1L << 3)
#define R6_EVENT_CONN_FAIL 				(1L << 4)
#define R6_EVENT_SEND_FAIL 				(1L << 5)
#define R6_EVENT_DOMAIN_OK    	        (1L << 6)

static at_evt_cb_t at_evt_cb_set[] = {
    [AT_SOCKET_EVT_RECV] = NULL,
    [AT_SOCKET_EVT_CLOSED] = NULL,
};

static void at_tcp_ip_errcode_parse(int result)
{
	switch(result)
	{
		case 0		: LOG_D("%d : No error",																result);break;
		case 1		: LOG_E("%d : EPERM - Operation not permitted",											result);break;
		case 2		: LOG_E("%d : ENOENT - No such resource",												result);break;
		case 4		: LOG_E("%d : EINTR - Interrupted system call",											result);break;
		case 5		: LOG_E("%d : EIO - I/O error",															result);break;
		case 9		: LOG_E("%d : EBADF - Bad file descriptor",												result);break;
		case 10		: LOG_E("%d : ECHILD - No child processes",												result);break;
		case 11		: LOG_E("%d : EWOULDBLOCK / EAGAIN - Current operation would block, try again",			result);break;
		case 12		: LOG_E("%d : ENOMEM - Out of memory",													result);break;
		case 14		: LOG_E("%d : EFAULT - Bad address",													result);break;
		case 22		: LOG_E("%d : EINVAL - Invalid argument",												result);break;
		case 32		: LOG_E("%d : EPIPE - Broken pipe",														result);break;
		case 77		: LOG_E("%d : EBADFD - File descriptor in bad state",									result);break;
		case 89		: LOG_E("%d : EDESTADDRREQ - Destination address required",								result);break;
		case 99		: LOG_E("%d : EADDRNOTAVAIL - Cannot assign requested address",							result);break;
		case 100	: LOG_E("%d : ENETDOWN - Network is down",												result);break;
		case 101	: LOG_E("%d : ENETUNREACH - Network is unreachable",									result);break;
		case 102	: LOG_E("%d : ENETRESET - Network dropped connection because of reset",					result);break;
		case 103	: LOG_E("%d : ECONNABORTED - Software caused connection abort",							result);break;
		case 104	: LOG_E("%d : ECONNRESET - Connection reset by peer",									result);break;
		case 105	: LOG_E("%d : ENOBUFS - No buffer space available ",									result);break;
		case 106	: LOG_E("%d : EISCONN - Transport endpoint is already connected",						result);break;
		case 107	: LOG_E("%d : ENOTCONN - Transport endpoint is not connected",							result);break;
		case 108	: LOG_E("%d : ESHUTDOWN - Cannot send after transport endpoint shutdown",				result);break;
		case 110	: LOG_E("%d : ETIMEDOUT - Connection timed out",										result);break;
		case 111	: LOG_E("%d : ECONNREFUSED - Connection refused",										result);break;
		case 112	: LOG_E("%d : EHOSTDOWN - Host is down",												result);break;
		case 113	: LOG_E("%d : EHOSTUNREACH - No route to host",											result);break;
		case 115	: LOG_E("%d : EINPROGRESS - Operation now in progress",									result);break;

	}
}

static int r6_socket_event_send(struct at_device *device, uint32_t event)
{
    return (int)rt_event_send(device->socket_event, event);
}

static int r6_socket_event_recv(struct at_device *device, uint32_t event, uint32_t timeout, rt_uint8_t option)
{
    int result = RT_EOK;
    rt_uint32_t recved;

    result = rt_event_recv(device->socket_event, event, option | RT_EVENT_FLAG_CLEAR, timeout, &recved);
    if (result != RT_EOK) {
        return -RT_ETIMEOUT;
    }

    return recved;
}

/**
 * close socket by AT commands.
 *
 * @param current socket
 *
 * @return  0: close socket success
 *         -1: send AT commands error
 *         -2: wait socket event timeout
 *         -5: no memory
 */
static int r6_socket_close(struct at_socket *socket)
{
    int result = RT_EOK;
    at_response_t resp = RT_NULL;
    int device_socket = (int) socket->user_data;
    struct at_device *device = (struct at_device *) socket->device;

    resp = at_create_resp(64, 0, 5 * RT_TICK_PER_SECOND);
    if (resp == RT_NULL) {
        LOG_E("no memory for resp create.");
        return -RT_ENOMEM;
    }

    /* default connection timeout is 10 seconds, but it set to 1 seconds is convenient to use.*/
    result = at_obj_exec_cmd(device->client, resp, "AT+USOCL=%d,1", device_socket);

    if (resp) {
        at_delete_resp(resp);
    }

    return result;
}

/**
 * create TCP/UDP client or server connect by AT commands.
 *
 * @param socket current socket
 * @param ip server or client IP address
 * @param port server or client port
 * @param type connect socket type(tcp, udp)
 * @param is_client connection is client
 *
 * @return   0: connect success
 *          -1: connect failed, send commands error or type error
 *          -2: wait socket event timeout
 *          -5: no memory
 */
static int r6_socket_connect(struct at_socket *socket, char *ip, int32_t port, enum at_socket_type type, rt_bool_t is_client)
{
    uint32_t event = 0;
    rt_bool_t retryed = RT_FALSE;
    at_response_t resp = RT_NULL;
    int result = RT_EOK, event_result = 0;
    int device_socket = (int)socket->user_data;
    struct at_device *device = (struct at_device *)socket->device;

    RT_ASSERT(ip);
    RT_ASSERT(port >= 0);

    resp = at_create_resp(128, 0, 5 * RT_TICK_PER_SECOND);
    if (resp == RT_NULL) {
        LOG_E("no memory for r6 device(%s) response structure.", device->name);
        return -RT_ENOMEM;
    }

__retry:

    /* clear socket connect event */
    event = SET_EVENT(device_socket, R6_EVENT_CONN_OK | R6_EVENT_CONN_FAIL);
    r6_socket_event_recv(device, event, 0, RT_EVENT_FLAG_OR);

    if (is_client) {
        switch (type)
        {
        case AT_SOCKET_TCP:
            /* send AT commands(eg: AT+USOCO=<n>,<ip>,<port>) to connect TCP server */
            if (at_obj_exec_cmd(device->client, resp,
                                "AT+USOCO=%d,%s,%d", device_socket, ip, port) < 0) {
                result = -RT_ERROR;
                goto __exit;
            }
            break;
            /* send AT commands(eg: AT+USOCO=<n>,<ip>,<port>) to connect UDP server */
        case AT_SOCKET_UDP:
            if (at_obj_exec_cmd(device->client, resp,
                                "AT+USOCO=%d,%s,%d", device_socket, ip, port) < 0) {
                result = -RT_ERROR;
                goto __exit;
            }
            break;

        default:
            LOG_E("r6 device(%s) not supported connect type : %d.", device->name, type);
            result = -RT_ERROR;
            goto __exit;
        }
    }

    /* waiting result event from AT URC, the device default connection timeout is 75 seconds, but it set to 10 seconds is convenient to use */
    if (r6_socket_event_recv(device, SET_EVENT(device_socket, 0), 10 * RT_TICK_PER_SECOND, RT_EVENT_FLAG_OR) < 0) {
        LOG_E("r6 device(%s) socket(%d) connect failed, wait connect result timeout.", device->name, device_socket);
        result = -RT_ETIMEOUT;
        goto __exit;
    }
    /* waiting OK or failed result */
    event_result = r6_socket_event_recv(device,
                                         R6_EVENT_CONN_OK | R6_EVENT_CONN_FAIL, 1 * RT_TICK_PER_SECOND, RT_EVENT_FLAG_OR);
    if (event_result < 0) {
        LOG_E("r6 device(%s) socket(%d) connect failed, wait connect OK|FAIL timeout.", device->name, device_socket);
        result = -RT_ETIMEOUT;
        goto __exit;
    }
    /* check result */
    if (event_result & R6_EVENT_CONN_FAIL) {
        if (retryed == RT_FALSE) {
            LOG_D("r6 device(%s) socket(%d) connect failed, maybe the socket was not be closed at the last time and now will retry.",
                  device->name, device_socket);
            if (r6_socket_close(socket) < 0) {
                result = -RT_ERROR;
                goto __exit;
            }
            retryed = RT_TRUE;
            goto __retry;
        }
        LOG_E("r6 device(%s) socket(%d) connect failed.", device->name, device_socket);
        result = -RT_ERROR;
        goto __exit;
    }

__exit:
    if (resp) {
        at_delete_resp(resp);
    }

    return result;
}

/**
 * send data to server or client by AT commands.
 *
 * @param socket current socket
 * @param buff send buffer
 * @param bfsz send buffer size
 * @param type connect socket type(tcp, udp)
 *
 * @return >=0: the size of send success
 *          -1: send AT commands error or send data error
 *          -2: waited socket event timeout
 *          -5: no memory
 */
static int r6_socket_send(struct at_socket *socket, const char *buff, size_t bfsz, enum at_socket_type type)
{
    uint32_t event = 0;
    int result = RT_EOK, event_result = 0;
    size_t cur_pkt_size = 0, sent_size = 0;
    at_response_t resp = RT_NULL;
    int device_socket = (int)socket->user_data;
    struct at_device *device = (struct at_device *)socket->device;
	struct at_device_r6 *r6 = (struct at_device_r6 *) device->user_data;
    rt_mutex_t lock = device->client->lock;

    RT_ASSERT(buff);

    resp = at_create_resp(128, 2, 5 * RT_TICK_PER_SECOND);
    if (resp == RT_NULL) {
        LOG_E("no memory for r6 device(%s) response structure.", device->name);
        return -RT_ENOMEM;
    }

    rt_mutex_take(lock, RT_WAITING_FOREVER);
	
    /* set current socket for send URC event */
    r6->user_data = (void *) device_socket;
	
    /* clear socket connect event */
    event = SET_EVENT(device_socket, R6_EVENT_SEND_OK | R6_EVENT_SEND_FAIL);
    r6_socket_event_recv(device, event, 0, RT_EVENT_FLAG_OR);

    /* set AT client end sign to deal with '>' sign.*/
    at_obj_set_end_sign(device->client, '>');

    while (sent_size < bfsz) {
        if (bfsz - sent_size < R6_MODULE_SEND_MAX_SIZE) {
            cur_pkt_size = bfsz - sent_size;
        } else {
            cur_pkt_size = R6_MODULE_SEND_MAX_SIZE;
        }
		
		/* send the "AT+USOWR" commands to AT server than receive the '>' response on the first line. */
        if (at_obj_exec_cmd(device->client, resp, "AT+USOWR=%d,%d", device_socket) < 0) {
            result = -RT_ERROR;
            goto __exit;
        }

        /* send the real data to server or client */
        result = (int)at_client_obj_send(device->client, buff + sent_size, cur_pkt_size);
        if (result == 0) {
            result = -RT_ERROR;
            goto __exit;
        }

        /* waiting result event from AT URC */
        if (r6_socket_event_recv(device, SET_EVENT(device_socket, 0), 15 * RT_TICK_PER_SECOND, RT_EVENT_FLAG_OR) < 0) {
            LOG_E("r6 device(%s) socket(%d) send failed, wait connect result timeout.", device->name, device_socket);
            result = -RT_ETIMEOUT;
            goto __exit;
        }
        /* waiting OK or failed result */
        event_result = r6_socket_event_recv(device,
                                             R6_EVENT_SEND_OK | R6_EVENT_SEND_FAIL, 5 * RT_TICK_PER_SECOND, RT_EVENT_FLAG_OR);
        if (event_result < 0) {
            LOG_E("r6 device(%s) socket(%d) send failed, wait connect OK|FAIL timeout.", device->name, device_socket);
            result = -RT_ETIMEOUT;
            goto __exit;
        }
        /* check result */
        if (event_result & R6_EVENT_SEND_FAIL) {
            LOG_E("r6 device(%s) socket(%d) send failed.", device->name, device_socket);
            result = -RT_ERROR;
            goto __exit;
        }

        sent_size += cur_pkt_size;
    }

__exit:
    /* reset the end sign for data conflict */
    at_obj_set_end_sign(device->client, 0);

    rt_mutex_release(lock);

    if (resp) {
        at_delete_resp(resp);
    }

    return result;
}

/**
 * domain resolve by AT commands.
 *
 * @param name domain name
 * @param ip parsed IP address, it's length must be 16
 *
 * @return  0: domain resolve success
 *         -1: send AT commands error or response error
 *         -2: wait socket event timeout
 *         -5: no memory
 */
static int r6_domain_resolve(const char *name, char ip[16])
{
#define RESOLVE_RETRY 3

    int i, result = RT_EOK;
    char recv_ip[16] = {0};
    at_response_t resp = RT_NULL;
    struct at_device *device = RT_NULL;

    RT_ASSERT(name);
    RT_ASSERT(ip);

    device = at_device_get_first_initialized();
    if (device == RT_NULL) {
        LOG_E("get first initialization r6 device failed.");
        return -RT_ERROR;
    }

    /* The maximum response time is 60 seconds, but it set to 30 seconds is convenient to use. */
    resp = at_create_resp(128, 4, 30 * RT_TICK_PER_SECOND);
    if (resp == RT_NULL) {
        LOG_E("no memory for r6 device(%s) response structure.", device->name);
        return -RT_ENOMEM;
    }

	/* clear R6_EVENT_DOMAIN_OK */
    r6_socket_event_recv(device, R6_EVENT_DOMAIN_OK, 0, RT_EVENT_FLAG_OR);

    result = at_obj_exec_cmd(device->client, resp, "AT+UDNSRN=0,\"%s\"", name);
    if (result < 0) {
        goto __exit;
    }
	
    if (result == RT_EOK) {
        for(i = 0; i < RESOLVE_RETRY; i++) {
            /* waiting result event from AT URC, the device default connection timeout is 60 seconds.*/
            if (r6_socket_event_recv(device, R6_EVENT_DOMAIN_OK, 10 * RT_TICK_PER_SECOND, RT_EVENT_FLAG_OR) < 0) {
                continue;
            } else {
                struct at_device_r6 *r6 = (struct at_device_r6 *) device->user_data;
                char *recv_ip = (char *) r6->socket_data;

                if (rt_strlen(recv_ip) < 8) {
                    rt_thread_mdelay(100);
                    /* resolve failed, maybe receive an URC CRLF */
                    result = -RT_ERROR;
                    continue;
                } else {
                    rt_strncpy(ip, recv_ip, 15);
                    ip[15] = '\0';
                    result = RT_EOK;
                    break;
                }
            }
        }

        /* response timeout */
        if (i == RESOLVE_RETRY) {
            result = -RT_ENOMEM;
        }
    }

 __exit:
    if (resp) {
        at_delete_resp(resp);
    }

    return result;
}
/**
 * set AT socket event notice callback
 *
 * @param event notice event
 * @param cb notice callback
 */
static void r6_socket_set_event_cb(at_socket_evt_t event, at_evt_cb_t cb)
{
    if (event < sizeof(at_evt_cb_set) / sizeof(at_evt_cb_set[1])) {
        at_evt_cb_set[event] = cb;
    }
}

static void urc_connect_func(struct at_client *client, const char *data, rt_size_t size)
{
    int device_socket = 0, result = 0;
    struct at_device *device = RT_NULL;
    char *client_name = client->device->parent.name;

    RT_ASSERT(data && size);

    device = at_device_get_by_name(AT_DEVICE_NAMETYPE_CLIENT, client_name);
    if (device == RT_NULL) {
        LOG_E("get device(%s) failed.", client_name);
        return;
    }

    sscanf(data, "+USOCO: %d,%d", &device_socket , &result);

    if (result == 0) {
        r6_socket_event_send(device, SET_EVENT(device_socket, R6_EVENT_CONN_OK));
    } else {
        at_tcp_ip_errcode_parse(result);
        r6_socket_event_send(device, SET_EVENT(device_socket, R6_EVENT_CONN_FAIL));
    }
}

static void urc_send_func(struct at_client *client, const char *data, rt_size_t size)
{
    int device_socket = 0;
    struct at_device *device = RT_NULL;
    struct at_device_r6 *r6 = RT_NULL;
    char *client_name = client->device->parent.name;

    RT_ASSERT(data && size);

    device = at_device_get_by_name(AT_DEVICE_NAMETYPE_CLIENT, client_name);
    if (device == RT_NULL) {
        LOG_E("get device(%s) failed.", client_name);
        return;
    }
    r6 = (struct at_device_r6 *) device->user_data;
    device_socket = (int) r6->user_data;

    if (rt_strstr(data, "SEND OK")) {
        r6_socket_event_send(device, SET_EVENT(device_socket, R6_EVENT_SEND_OK));
    } else if (rt_strstr(data, "SEND FAIL")) {
        r6_socket_event_send(device, SET_EVENT(device_socket, R6_EVENT_SEND_FAIL));
    }
}

static void urc_close_func(struct at_client *client, const char *data, rt_size_t size)
{
    int device_socket = 0;
    struct at_socket *socket = RT_NULL;
    struct at_device *device = RT_NULL;
    char *client_name = client->device->parent.name;

    RT_ASSERT(data && size);

    device = at_device_get_by_name(AT_DEVICE_NAMETYPE_CLIENT, client_name);
    if (device == RT_NULL) {
        LOG_E("get device(%s) failed.", client_name);
        return;
    }

    /* get the current socket by receive data */
    sscanf(data, "%d,%*s", &device_socket);

    if (rt_strstr(data, "OK")) {
        r6_socket_event_send(device, SET_EVENT(device_socket, R6_EVNET_CLOSE_OK));
    } else if (rt_strstr(data, "DISCONNECT")) {
        struct at_socket *socket = RT_NULL;

        /* get AT socket object by device socket descriptor */
        socket = &(device->sockets[device_socket]);

        /* notice the socket is disconnect by remote */
        if (at_evt_cb_set[AT_SOCKET_EVT_CLOSED]) {
            at_evt_cb_set[AT_SOCKET_EVT_CLOSED](socket, AT_SOCKET_EVT_CLOSED, RT_NULL, 0);
        }
    }
}

static void urc_recv_func(struct at_client *client, const char *data, rt_size_t size)
{
    int device_socket = 0;
    rt_int32_t timeout;
    rt_size_t bfsz = 0, temp_size = 0;
    char *recv_buf = RT_NULL, temp[8] = {0};
    struct at_socket *socket = RT_NULL;
    struct at_device *device = RT_NULL;
    char *client_name = client->device->parent.name;

    RT_ASSERT(data && size);

    device = at_device_get_by_name(AT_DEVICE_NAMETYPE_CLIENT, client_name);
    if (device == RT_NULL) {
        LOG_E("get device(%s) failed.", client_name);
        return;
    }

    /* get the current socket and receive buffer size by receive data */
    sscanf(data, "+QIURC: \"recv\",%d,%d", &device_socket, (int *) &bfsz);
    /* set receive timeout by receive buffer length, not less than 10 ms */
    timeout = bfsz > 10 ? bfsz : 10;

    if (device_socket < 0 || bfsz == 0) {
        return;
    }

    recv_buf = (char *) rt_calloc(1, bfsz);
    if (recv_buf == RT_NULL) {
        LOG_E("no memory for URC receive buffer(%d).", bfsz);
        /* read and clean the coming data */
        while (temp_size < bfsz) {
                if (bfsz - temp_size > sizeof(temp)) {
                    at_client_obj_recv(client, temp, sizeof(temp), timeout);
                } else {
                    at_client_obj_recv(client, temp, bfsz - temp_size, timeout);
                }
                temp_size += sizeof(temp);
        }
        return;
    }

    /* sync receive data */
    if (at_client_obj_recv(client, recv_buf, bfsz, timeout) != bfsz) {
        LOG_E("%s device receive size(%d) data failed.", device->name, bfsz);
        rt_free(recv_buf);
        return;
    }

    /* get at socket object by device socket descriptor */
    socket = &(device->sockets[device_socket]);

    /* notice the receive buffer and buffer size */
    if (at_evt_cb_set[AT_SOCKET_EVT_RECV]) {
        at_evt_cb_set[AT_SOCKET_EVT_RECV](socket, AT_SOCKET_EVT_RECV, recv_buf, bfsz);
    }
}

/* r6 device URC table for the socket data */
static const struct at_urc urc_table[] =
{
    {"+TCPSETUP:", "\r\n", urc_connect_func},
    {"+UDPSETUP:", "\r\n", urc_connect_func},
    {"+TCPSEND:", "\r\n", urc_send_func},
    {"+UDPSEND:", "\r\n", urc_send_func},
    {"+TCPCLOSE:", "\r\n", urc_close_func},
    {"+UDPCLOSE:", "\r\n", urc_close_func},
    {"+TCPRECV:", "\r\n", urc_recv_func},
    {"+UDPRECV:", "\r\n", urc_recv_func},
};

static const struct at_socket_ops r6_socket_ops =
{
	r6_socket_connect,
	r6_socket_close,
	r6_socket_send,
	r6_domain_resolve,
	r6_socket_set_event_cb,
#if defined(AT_SW_VERSION_NUM) && AT_SW_VERSION_NUM > 0x10300
    RT_NULL,
#endif
};

int r6_socket_init(struct at_device *device)
{
    RT_ASSERT(device);

    /* register URC data execution function  */
    at_obj_set_urc_table(device->client, urc_table, sizeof(urc_table) / sizeof(urc_table[0]));

    return RT_EOK;
}

int r6_socket_class_register(struct at_device_class *class)
{
    RT_ASSERT(class);

    class->socket_num = AT_DEVICE_R6_SOCKETS_NUM;
    class->socket_ops = &r6_socket_ops;

    return RT_EOK;
}

#endif /* AT_DEVICE_USING_r6 && AT_USING_SOCKET */
